#include <fstream>
#include <iostream>
#include <vector>

using namespace std;

ifstream f("lca.in");
ofstream g("lca.out");

const int nmax = 100005, sqn = 315;
int n, m, x, y, i, v, tt[nmax], ttsq[nmax], niv[nmax], nivsq[nmax];
vector <int> ls[nmax];

void dfs(int x) {
    int l = ls[x].size(), i, y;
    niv[x] = niv[tt[x]] + 1;
    if (niv[x]%sqn == 0) {
        ttsq[x] = tt[x], nivsq[x] = nivsq[tt[x]]+1;
    } else ttsq[x] = ttsq[ tt[x] ], nivsq[x] = nivsq[ tt[x] ];

    for (i = 0; i < l; i++) {
        y = ls[x][i];
        dfs(y);
    }
}

int lca(int x, int y) {
    while (ttsq[x] != ttsq[y]) {
        if (nivsq[x] > nivsq[y]) x = ttsq[x];
        else y = ttsq[y];
    }

    while (x != y) {
        if (niv[x] > niv[y]) x = tt[x];
        else y = tt[y];
    }
    return x;
}

int main() {
    f >> n >> m;
    for (i = 2; i <= n; i++) {
        f >> x;
        tt[i] = x;
        ls[x].push_back(i);
    }
    niv[1] = 1;
    dfs(1);

    while (m--) {
        f >> x >> y;
        g << lca(x, y) << '\n';
    }
    return 0;
}